Covid vaccine effectiveness may decline over time with cases of the highly contagious Delta Covid variant still circulating, according to new research from the Centres for Disease Control and Prevention (CDC). A study released this week showed vaccine effectiveness decreased among health care workers who were fully vaccinated since the time the Delta variant became widespread, which could be due to waning effectiveness of the vaccine over time.
Dr Amir said the vaccines still offer good protection and urged people to still go forward and get it.
He explained: “The study here shows that after six months the protection the two vaccines offer does wane slightly.
“So the Pfizer vaccine, that protection drops from 88 percent to 74 percent.
“For the AstraZeneca vaccine, it’s 77 to 67 percent.
Dr Amir said there may be an argument for booster shots, particularly for the clinically extremely vulnerable.
But he still thinks there needs to be more data on booster shots.
He continued: “We need to start vaccinating parts of the world that haven’t been vaccinated at all before we offer a third vaccine to those who have good protection already.
“So don’t worry about this, still go and get vaccinated.”
A new study will investigate whether a third dose of vaccine for people with weakened immune systems gives a stronger immune response than two doses.
The study, OCTAVE DUO, will offer people who are immunosuppressed or immunocompromised a Pfizer, Moderna or Novavax vaccine to determine whether this will give a stronger immune response than 2 doses.
The £2.2 million study will build on the OCTAVE trial, led by the University of Glasgow and co-ordinated by the University of Birmingham’s Cancer Research UK Clinical Trials Unit.
Health and Social Care Secretary Sajid Javid said: “Vaccines have built a strong wall of defence in the UK and this is allowing most of us to learn to live safely with COVID-19.
“We know some people may get less protection from the vaccine than others, so we are planning for a booster programme in the autumn, prioritising those most at risk.
“This new study will play an important role in helping to shape the deployment of future vaccines doses for these specific at-risk groups.”